The present invention relates generally to automotive vehicle seating and, more particularly, to an automotive vehicle seat assembly equipped with a manually operable six-way seat adjustment mechanism.
Traditionally, only the most expensive luxury vehicles have been equipped with seating systems that are selectively adjustable in multiple directions in addition to fore and aft adjustment. However, in light of recent consumer demands, most automobile manufacturers have found it necessary to offer enhanced seat adjustment capabilities on even the least expensive motor vehicles. Since the cost and weight penalties associated with conventional power seat adjustments systems make their application on smaller, less expensive vehicles generally impractical, the use of a manually-operable seat adjustment mechanism is largely dictated for such applications.
One type of manually-operable seat adjustment mechanism known in the art is commonly referred to as a "six-way" mechanism which is operable to provide independent height adjustment (i.e. up and down) for the front and rear portions of the seat member in addition to "fore and aft" longitudinal adjustment of the entire seat assembly. Generally, one or more actuation levers are provided which the seat occupant must manipulate to adjust the seat assembly to the desired comfort position. While most "six-way" seat adjustment mechanisms function satisfactorily, there remains a continuing need to improve their operation and reliability concomitantly with a reduction in structural complexity and manufacturing related costs.
In addition, the use of occupant impact protection or "restraint" systems are mandated for virtually all passenger-type motor vehicles. Traditionally, such restraint systems typically include a seat belt assembly for restraining the seat occupant during an emergency situation, such as during heavy braking or a vehicular collision. In many instances, the retractable seat belt and seat belt buckle are anchored directly to the floor pan of the motor vehicle along opposite lateral sides of the seat adjustment mechanism. Therefore, when the seat occupant adjusts the horizontal "fore and aft" position of the seat assembly, via selectively actuating the manually-operable seat adjustment mechanism, the seat belt tends to tighten or loosen relative to the seat occupant depending on the direction of longitudinal adjustment. As a result, the seat occupant is typically required to re-adjust the seat belt assembly to provide the proper restraint and comfort following seat adjustment.
In order to avoid the inconveniences associated with adjustable seat systems having floor mounted seat belt buckles, it is desirable to anchor the seat belt buckle to the seat adjustment mechanism for movement with the seat assembly during fore and aft positional adjustment. However, in order to incorporate a "travelling" seat belt buckle into a seat adjustment mechanism, it is required that such systems strictly comply with stringent strength requirements to insure adequate occupant restraint during vehicle emergency or impact conditions. This is due to the increased loading imposed on the seat belt buckle which is, in turn, transferred to the seat adjustment mechanism. Accordingly, there is also a continuing need to develop six-way seat adjustment mechanisms incorporating improved travelling seat belt buckle anchorage arrangements which possess the necessary structural and functional characteristics and which can be manufactured in a highly cost effective manner.